The field of the invention pertains to the selective functionalizing of a hydrocarbon at its primary Cxe2x80x94H site by thermally reacting a functionalizing reagent and the hydrocarbon in the presence of an transition metal catalyst.
Aliphatic compounds, and especially alkanes, are among the most abundant but least reactive molecules. Chemical synthesis relies on reactions that form one product selectively, and few reactions involving aliphatic compounds such as alkanes occur in this fashion. Radical reactions, such as halogenations and autoxidations, typically produce mixtures of products; even enzymes do not react regiospecifically with linear alkanes. Transition metal compounds are known to react with alkanes to give terminal alkyl complexes selectively, but these reactions are typically stoichiometric in metal. Transition metal-catalyzed dehydrogenation suffers from unfavorable thermodynamics and isomerization of terminal to internal alkenes during the reaction. Carbonylation of alkanes is also endothermic, and the photochemical processes produce secondary photoproducts.
Several years ago, it was reported in K. M. Waltz; C. N. Muhoro, J. F. Hartwig, Organometallics, 1999, 21 and in K. Waltz, J. F. Hartwig, Science 1997, 277, 211, that low valent transition metal complexes containing boryl ligands reacted with hydrocarbons, including alkanes, by photochemical dissociation of ligand to produce functionalized hydrocarbons. It was reported that organoboronate esters were formed in a stoichiometric fashion by the regiospecific replacement of one hydrogen on a terminal position with a boryl group. It was also reported in H.Chen, J. F. Hartwig, Angew.Chem.Int.Ed.Engl 1999 that commercially available R2BBR2 (R2=pinacolate) reagents and substituted cyclopentadienyl (Cp*) Re(CO)3 would catalytically convert alkanes to alkylboronate esters under photochemical reaction conditions. Photochemical processes, however, are impractical at an industrial scale.
It is desirable to functionalize regiospecifically an aliphatic compounds at its terminal Cxe2x80x94H site. It is also desirable that the process for the functionalization occur thermally rather than through other means such as photochemical processes. It is also an object of the invention to manufacture a functionalized aliphatic compounds, and especially a functionalized alkane, by a process which is catalytic rather than stoichiometric in metal.
There is now provided a process for the catalytic coupling of aliphatic hydrocarbons with certain reagents under thermal conditions to selectively functionalize the aliphatic hydrocarbon at its terminal Cxe2x80x94H site.
In one embodiment, there is provided a process for selectively functionalizing an aliphatic or alkyl branched alicyclic hydrocarbon at a primary Cxe2x80x94H hydrocarbon bond comprising thermally reacting a functionalizing reagent and the hydrocarbon in the presence of a catalyst, said catalyst comprising:
a) a source of a transition metal;
b) a source of a 3 to 8, cyclic or non-cyclic, aromatic or non-aromatic, neutral, cationic or anionic, substituted or unsubstituted electron donor moiety which does not dissociate under thermal reaction conditions, wherein said moiety
(i) lacks aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or
(ii) contains sterically hindered aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal; and
c) a source of ligands capable of formally donating an electron pair to the transition metal a) and which dissociate thermally;
and wherein said functionalizing reagent comprises a source of boron.
In another embodiment, there is provided a catalytic process having more than 50 turnovers comprising thermally activating said catalyst in the presence of a functionalizing reagent and an alipahtic or alkyl branched alicyclic hydrocarbon containing primary Cxe2x80x94H bonds, said catalyst comprising:
a) a source of a transition metal;
b) a source of a 3 to 8, cyclic or non-cyclic, aromatic or non-aromatic, neutral, cationic or anionic, substituted or unsubstituted electron donor moiety which does not dissociate under thermal reaction conditions, wherein said moiety
(i) lacks aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or
(ii) contains sterically hindered aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal; and
c) a source of ligands capable of formally donating an electron pair to the transition metal a) and which dissociate thermally;
and wherein said functionalizing reagent comprises a source of B, C, N, O, Si, P, S, Ge, As, Al, or Se.
In yet another embodiment of the invention, there is provided a functionalization process comprising selectively functionalizing 80% or more of primary Cxe2x80x94H hydrocarbon bonds in a hydrocarbon composition in the presence of a thermally activated catalyst, wherein said process turns over the catalyst 50 or more times.
Preferably, the catalyst composition used in the process of the invention is comprised of, or obtained by combining a source of the following in any sequence:
a) a source of a transition metal;
b) a source of a 3 to 8, cyclic or non-cyclic, aromatic or non-aromatic, neutral, cationic or anionic, substituted or unsubstituted electron donor moiety which does not dissociate under thermal reaction conditions, wherein said moiety
(i) lacks aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or
(ii) contains sterically hindered Cxe2x80x94H bonds on the moiety directly bonded to the transition metal; and
c) a source of ligands comprising trialkylsilanes, unsaturated aliphatic compounds, xcfx80 allyl compounds, or xcfx80 arene compounds, wherein said xcfx80 arene compounds
(i) lack aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or
(ii) contain sterically hindered aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal.
A more preferred catalyst used in the process of the invention comprises, or is obtained by combining a source of the following in any sequence:
a) Rh or Ir;
b) a fully substituted cyclic C5 moiety having a xcfx80-coordinated electronic structure and lacking aromatic Cxe2x80x94H bonds; and
c) ligands comprising aliphatic unsaturated or xcfx80 arene compounds, and wherein said xcfx80 arene compounds
(i) lack aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or
(ii) contain sterically hindered aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal.
There is further provided a functionalization process comprising selectively functionalizing 80% or more of primary Cxe2x80x94H hydrocarbon bonds in a hydrocarbon composition in the presence of a thermally activated catalyst and a functionalizing reagent, wherein said functionalizing reagent comprises a compound containing a moiety represented by the following structure: 
The process of the invention is 80% or more selective toward functionalizing a primary Cxe2x80x94H bond on hydrocarbon molecules, is catalytic, and relies ton thermal rather than photolytic or photochemical processes to supply the activation energy required for dissociating the ligand from the catalyst. The reaction proceeds in a straightforward manner in that a hydrocarbon, a catalyst, and a functionalizing reagent are contacted in a reaction vessel and heated to a temperature effective to activate the reaction towards the functionalization of the hydrocarbon at its primary Cxe2x80x94H site. The nature of the catalyst and functionalizing reagent as described in further detail below enable one to manufacture selectively and thermally a hydrocarbon functionalized at its primary Cxe2x80x94H site.
In the process of the invention, the hydrocarbon is functionalized at a terminal Cxe2x80x94H bond in the presence of a catalyst and a functionalizing reagent. The catalyst used in the reaction must be one which is capable of being thermally activated, and the process functionalizes the terminal Cxe2x80x94H bond of a hydrocarbon by thermally activating the catalyst. By thermal activation of the catalyst is meant the process of dissociating a c) ligand from a metal center by application of heat below the temperature at which the Z ligand (described below) dissociates from the metal center, and at least above the temperature of the environment at which the functionalizing reagent is stored.
A useful screening technique to determine whether a catalyst will activate a primary Cxe2x80x94H bond is as follows. The catalyst one desires to employ is mixed with a deuterated ligand at a molar ratio within the range of 1:1 to 1:10 in the presence of an appropriate solvent, such as decane or cyclohexane-d12. The mixture is analyzed by 31P NMR, 11B NMR, 1H NMR, and 2H NMR. The mixture is subsequently reacted solely by application of heat for 48 hours or less at no more than reaction pressures and at a temperature at which reaction takes place but below the temperature at which the b) moiety and c) ligands dissociate from the metal center. Analytical results of a catalyst which has been thermally activated will show the formation of a peak corresponding to free dissociated ligand and the formation of a deuterated catalyst, and the reduction or elimination of peaks corresponding to the presence of free deuterated ligand.
A useful screening test to determine whether a catalyst is one which is capable of being activated thermally is to conduct the reaction in the dark.
Although other compounds which chemically react to assist the dissociation of the c) ligand may be used along with the catalyst in the process of functionalizing an hydrocarbon, the catalyst used in the process must be of a type which is capable of being thermally activated in the absence of any compound which chemically reacts with the reagent to assist the activation of the reagent. Accordingly, a process which applies heat in addition to other activation mechanisms, such as chemical or photolytic means, and successfully activates the catalyst is nevertheless a process within the scope of the invention if the particular catalyst is capable of thermally functionalizing the hydrocarbon at a primary Cxe2x80x94H bond in the absence of a co-catalyst or photons.
Other published catalytic systems for activating alkanes at the primary Cxe2x80x94H bond require the presence of a sacrificial olefin to achieve high turnover numbers. An advantage of the process of the invention is that a sacrificial hydrogen acceptor is not required to provide a catalytic process with high turnover. Hydrogen released from the primary Cxe2x80x94H hydrocarbon bond does not readily react with the functionalized hydrocarbon under reaction conditions. Although the presence of hydrogen acceptors is not excluded from the invention, the process of the invention is capable of achieving high turnover numbers in the absence of a sacrificial hydrogen acceptor.
By a xe2x80x9cfunctionalizing reagentxe2x80x9d is generically meant to include any compound as described below which operates to functionalize a hydrocarbon""s primary Cxe2x80x94H bond, and is not meant to define the reaction mechanism, efficiency, or fate of the reagent compound itself.
Suitable hydrocarbon substrates which are functionalized in the process of the invention are any hydrocarbons containing a primary Cxe2x80x94H bond, also known as its terminal Cxe2x80x94H bond. By xe2x80x9cfunctionalizedxe2x80x9d is meant the replacement of H at a primary Cxe2x80x94H bond of a hydrocarbon with the functionalizing reagent residue. By a primary Cxe2x80x94H bond is meant any bond between a hydrogen atom and any carbon atom bearing two or more additional hydrogen atoms. The primary Cxe2x80x94H bond is to be distinguished from a secondary Cxe2x80x94H bonding site wherein the carbon atom is a secondary carbon atom and any functional group replacing its hydrogen atom would be considered a secondary functional molecule. It is to be understood that a xe2x80x9cbondxe2x80x9d as used throughout the specification means a covalent bond, a complex, a coordination, or any other form of a linkage between the stated atoms.
A hydrocarbon which is functionalized in the process of the invention is a saturated or unsaturated, branched or unbranched, substituted or unsubstituted aliphatic hydrocarbon (e.g. alkanes or alkenes); or a saturated or unsaturated, substituted or unsubstituted, alkyl branched alicyclic compounds, each having at least one primary Cxe2x80x94H bond, and which do not deactivate the catalyst at reaction temperatures. The hydrocarbons may be used singly or in mixture. The hydrocarbon composition contains aliphatic and/or alkyl branched alicyclic hydrocarbons, optionally mixed with other hydrocarbon molecules, such as aromatic compounds. The hydrocarbon composition preferably comprises at least 50 wt. % aliphatic or alkyl branched alicyclic hydrocarbons, preferably at least 75 wt. %, more preferably at least 90 wt. %, and most preferably at least 95 wt. % or more up to 100 wt. %.
The source of the hydrocarbon can be any commercial source available, such as from a refined crude oil source or a Fisher-Tropsch stream, and can be used in crude mixtures or at any level of refinement, any fraction containing alkanes, and at any purity. Further, any olefin having 3-30 carbon atoms, and their dimers or trimers are also useful hydrocarbons provided that the molecule has a terminal site having one saturated carbon atom. Alkyl branched alicyclic (e.g. branched cycloparaffins or cycloolefins) are also useful, so long as the alkyl group contains at least one saturated carbon atom containing a primary Cxe2x80x94H bond site.
In one embodiment, the hydrocarbon comprises a linear or branched alkane (by definition, having no unsaturation, cyclic or aryl moieties attached). Suitable examples of alkanes include those having 1-32 carbon atoms, advantageously 3-24, and particularly 6-18 carbon atoms. Examples of linear hydrocarbons include n-hexane, n-heptane, n-octane, n-nonane, n-dodecane, n-tridecane, n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-nonadecane, n-eicosane, and the like. Examples of branched aliphatic hydrocarbons include 2,2,3,3-tetra-methylbutane, 2,2,4-trimethylpentane, n-tricontane, 2-methylbutane, 2-methylpentane, 3-methylpentane, 2-methylhexane, 3-methylhexane, 2-methylheptane, 3-methylheptane, 4-methylheptane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2,2-dimethylpentane, 2,3-dimethylpentane, 4-dimethylpentane, 3,3-dimethylpentane, 2,2-dimethylhexane, 2,4-dimethylhexane, 2,5-dimethylhexane, 3,4-dimethylhexane, 2,3-dimethylheptane, other 2-methyl or ethyl-C6-C28 alkanes, mixtures thereof, and the like.
Examples of alkyl branched alicyclic hydrocarbons include methyl cyclohexane, methyl cyclooctane, ethyl cyclohexane, ethyl cyclooctane, isopropyl cyclohexane, and the like.
The hydrocarbon may contain heteroatoms within the hydrocarbon chain, such as oxygen or nitrogen. However, the number of heteroatoms is no more than 1 heteroatom for every 4 carbon atoms, preferably no more than 1 heteroatom for every 6 carbon atoms, and more preferably the hydrocarbon is free of heteroatoms.
The catalyst used in the process of the invention comprises:
a) a source of a transition metal;
b) a source of a 3 to 8, cyclic or non-cyclic, aromatic or non-aromatic, neutral, cationic or anionic, substituted or unsubstituted electron donor moiety which does not dissociate under thermal reaction conditions, wherein said moiety
(i) lacks aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or
(ii) contains sterically hindered aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal; and
c) a source of ligands capable of formally donating an electron pair to the transition metal a) and which dissociate thermally.
Preferably, the source of c) ligands comprise trialkylsilanes, unsaturated aliphatic compounds, xcfx80 allyls, or xcfx80 arene compounds, wherein said xcfx80 arene compounds
(i) lack aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or
(ii) contains sterically hindered aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal.
In an embodiment of the invention, the catalyst can be conveniently represented by any one of the following structures: 
wherein X and Y together represent the c) ligands bonded directly or indirectly to M, and wherein X and Y may be bridged to form a cyclic arene compound which may contain branches, substituents, or fused aromatic rings; M represents the a) transition metal center; Z represents a cyclic or non-cyclic, aromatic or non-aromatic, neutral, cationic or anionic, substituted or unsubstituted compound having a n-coordinated electronic structure and lacking aromatic Cxe2x80x94H bonds on the moiety which will directly bond to the transition metal a), R represents one or more optional substituents or branches, and n represents an integer ranging from 0 to 8. One or more of the ligands are bonded to the M metal center, and preferably more than one ligand is bonded to the metal center M. It is not critical to the invention that either the nature or location of the linkage between the ligands to the metal center be known, so long as some form of a linkage between the X or the X and Y ligands and the metal center exists at a position which will provide a catalyst which is effective to functionalize a primary Cxe2x80x94H hydrocarbon bond.
Suitable transition metals a) (or M) include transition metals in the +1, +2, +3, +4, +5, or +6 oxidation state. It is preferred to employ a transition metal that is capable of traversing 2 or more formal oxidation states, more preferably 4 or more formal oxidation states. Accordingly, it is preferred to employ a metal having a formal oxidation state prior to bonding with the b) compound and the c) ligand(s) of +4, +5, or +6. Examples of suitable transition metals include Fe, Co, Ni, Rh, Ru, Os, Pt, Pd, Mn, Re, W, Cr, Mo, Ir, and the metals from the lanthanide and actinide series. Preferred metals are Re, Rh, and Ir. More preferred are Rh and Ir, and most preferred is Rh to improve the reaction rate over Ir and to improve the conversion of the functionalizing reagent to the hydrocarbon-functionalizing reagent adduct and other byproducts. It is generally believed that Ir transition metal centers promote faster reaction rates and are more completely convert Cxe2x80x94H bonds than Rh using equivalent ligands and reaction conditions. Surprisingly, however, we have found that the reaction rate using Rh as a transition metal center to convert the functionalizing reagent to the functionalized hydrocarbon was faster and more complete than its Ir counterpart. Accordingly, in a most preferred embodiment, the transition metal is Rh.
The catalyst used in the process of the invention also comprises a source of a 3 to 8, cyclic or non-cyclic, aromatic or non-aromatic, neutral, cationic or anionic, substituted or unsubstituted electron donor moiety which does not dissociate under thermal reaction conditions, wherein said moiety
(i) lacks aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or
(ii) contains sterically hindered aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal;
The Z moiety depicted in the structural diagrams above (corresponding to the b) moiety) is a 3-8 electron donor ligand which does not dissociate under thermal reaction conditions. Thermal reaction conditions are all the physical reaction conditions employed in practice to functionalize the hydrocarbon at its primary Cxe2x80x94H site, including but not limited to the pressure, temperature, space velocity, etc. conditions within the reaction vessel. Dissociation of the Z moiety results in the degradation of the catalyst, thereby terminating its activity.
The Z moiety also donates electron density to stabilize the oxidation state of the transition metal of the active catalyst. Preferably, the electronic charge of the Z moiety will fully stabilize the metal center depending upon the oxidation state of the metal center M in its active state.
The Z moiety may be between an xcex72 and an xcex78 complexed cyclic or non-cyclic, aromatic or non-aromatic, neutral cationic or anionic, substituted or unsubstituted ligand. It is preferably a xcfx80 coordinated, cyclic aromatic compound fully substituted, and more preferably a cyclic, fully substituted aromatic, anionic moiety. In one embodiment, the Z compound is a fully substituted cyclic xcex75 5-8 carbon membered ring.
The Z moiety may be coordinated to the M metal center in several different isomeric configurations. For example, the Z moiety in the xcex75 configuration may be in one of the S, W, or U isomeric states. In a more preferred embodiment, the Z moiety is the U isomer in the xcex75 bonded configuration. It is to be understood that the original position of the double bonds of a dienyl ligand need not be identified because of the delocalization effect. For example, an xcex75-1,3-pentadien-3-yl group is identical to the xcex75-1,4-pentadien-3-yl group. It is to be further understood that all isomeric forms of Z moieties are included in any reference to a Z moiety identified herein. Furthermore, it is not critical to the invention that either the nature of the linkage between the Z moiety and the metal center, or the carbon number to which the Z moiety is coordinated, bonded, or completed to the metal center, be known, so long as some form of a linkage between the Z moiety and the metal center exists at a position which will provide a functionalizing reagent which is effective to functionalize a terminal Cxe2x80x94H bond.
The Z moiety must lack aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or contain sterically hindered aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal. An aromatic Cxe2x80x94H bond is a bond between a hydrogen atom and one of the carbon atoms forming the aromatic ring. The presence of sterically accessible aromatic Cxe2x80x94H bonds on the moiety which will directly bond to the transition metal a) is undesirable because they compete with the functionalization of the primary Cxe2x80x94H hydrocarbon bonds, thereby reducing the yield of functionalized hydrocarbon. Accordingly, the Z moiety should either altogether lack aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or if such aromatic Cxe2x80x94H bonds are present, they should be sterically inaccessible by other activated catalyst molecules in the vicinity to minimize or avoid functionalizing the Z moiety aromatic Cxe2x80x94H sites.
In a more preferred embodiment, every site on the Z moiety, including those sites which are directly and only indirectly bonded to the transition metal through a substituent on the Z moiety directly bonded to the transition metal, are either lacking in any aromatic Cxe2x80x94H bonds or contain sterically hindered Cxe2x80x94H sites.
It will be appreciated that suitable substituents are bulky groups which are generally regarded as sterically demanding. Non-limiting examples of such bulky substituents on aromatic ring carbon atoms adjacent to the aromatic Cxe2x80x94H site include hydrocarbyl, hydrocarbyl substituted metalloid radicals wherein the metalloid is selected from Group IV A or the Periodic Table, silyl, germyl, cyano, hydroxyl, amino, and halo groups, such as fluorine or chlorine, especially fluoro or fluoroalkyl groups, aryl, phenyl which optionally may bear one or more of the same or different substituents, alklaryl, alkoxy, phenoxy, phenylalkoxy, benzyl, bulky substituents containing one or more hetero atoms such as tri (loweralkyl)silyl, xe2x80x94NPh2, xe2x80x94NHPh, xe2x80x94BPh2, and xe2x80x94B(OPh)2, wherein n may be an integer of from 0 to 4, preferably from 0 to 2 and more preferably from 0 to 1, and m may be an integer of from 0 to 3, preferably from 0 to 2 and more preferably from 0 to 1, and carboxylic acid esters.
Any of the Z moiety substituents may be joined together on the Z moiety to form a C4-C20 saturated ring. Examples of hydrocarbyl groups include C1-C20 branched or unbranched alkyl groups, preferably C1-C6 branched or unbranched alkyl groups such as methyl, ethyl, isopropyl, propyl, butyl, t-butyl, isobutyl, neopentyl, and 3-phenyl-neopentyl. Other examples of hydrocarbyl groups include the C1-C20 substituted radicals, optionally where one or more of the hydrogen atoms may be replaced with a halogen radical, an amido radical, a phosphino radical, and an alkoxy radical or any other radical containing a Lewis acidic or basic functionality.
It is preferred that the subsitituent donate electron density to the ligand. Such substituents generally contribute to increasing the thermal stability of the catalyst under reaction conditions with the hydrocarbon, as well as increasing the activity of the catalyst.
Examples of preferred substituents comprise trimethylsilyl and C1-C4 branched or unbranched alkyl groups, such as methyl, isopropyl, t-butyl,.
The number of substituents is sufficient to create a fully substituted Z moiety or sufficiently substituted to sterically protect the remaining aromatic Cxe2x80x94H bonds. The aromatic carbon atoms which are substituted include those carbon atoms in aromatic nuclei fused to an aromatic ring bonded directly to the metal center M, as well as the aromatic nuclei indirectly tethered to the transition metal through the non-dissociating electron donating atoms directly bonded to the transition metal.
Examples of b) moieties (equivalent to the Z moeities) include, but are not limited to, methylcyclopentadiene, ethylcyclopentadiene, t-butylcyclopentadiene, hexylcyclopentadiene, octylcyclopentadiene, 1,2-dimethylcyclopentadiene, 1,3-dimethylcyclopentadiene, 2,4-dimethyl-xcex75-pentadien-1-yl, 1,5-dimethyl-xcex75-pentadien-2-yl, 2,4-dimethyl-xcex75-pentadien-3-yl, 1,5-dimethyl-5-pentadien-3-yl, 1,2,4-trimethylcyclopentadiene, pentamethylcyclopentadiene, 1, 5-bis(trimethylsilyl)-xcex75-pentadien-3-yl, 1,2,3,4-tetramethylcyclopentadiene, 1,2,6,6-tetramethyl-5-cyclohexadien-4-yl, 1,2,4,6,6-pentamethyl-xcex75-cyclohexadien-3-yl, 1,2,4,6,6-pentamethyl-xcex75-cyclohexadien-5-yl, 1,2,5,6,6-pentamethyl-xcex75-cyclohexadien-4-yl, 1,2,4,5,6,6-hexamethyl-xcex75-cyclohexadien-3-yl; 1,2,4,5-tetramethyl-6,6-cyclotrimethylene-xcex75-cyclohexadien-3-yl; 1,2-dihydronaphthalen-1-yl; 1,2-dihydronaphthalen-2-yl; 1,1-dimethyl-1,2-dihydronaphthalen-2-yl; 1,1-dimethyl-1,2-dihydronaphthalen-4-yl; diphenylmethyl-di(1-cyclohexenyl)methyl; 1,1-dimethyl-1,2,5,6,7,8-hexahydronaphthalen-4-yl; 1,1-dimethyl-1,4,5,6,7,8-hexahydronaphthalen-4-yl; 1,1-dimethyl-1,5,6,7,8,9-hexahydronaphthalen-4-yl; 1,1,2,3-tetramethyl-1,2,5,6,7,8-hexahydronaphthalen-4-yl; 1,1,2,3-tetramethyl-1,4,5,6,7,8-hexahydronaphthalen-4-yl; 1,1,2,3-tetramethyl-1,5,6,7,8,9-hexahydronaphthalen-4-yl; 9,10-dihydroanthracen-9-yl; 9,10-dihydroanthracen-1-yl; 9,9-dimethyl-9,10-dihydroanthracen-10-yl; 1,2,3,4,9,10-hexahydroanthracen-9-yl; 1,2,3,4,9,10-hexahydroanthracen-1-yl; 1,2,3,4,9,11-hexahydroanthracen-9-yl; 1,4,5,8,9,10-hexahydroanthracen-1-yl; 9,9-dimethyl-1,4,5,8,9,10-hexahydroanthracen-10-yl; 9,9-dimethyl-1,4,5,8,9,10-hexahydroanthracen-2-yl; 8,8-dimethyl-1,4,5,8,9,10-hexahydroanthracen-10-yl; 1,2,3,4,5,6,7,8,9,10-decahydroanthracen-9-yl; 1,2,3,4,5,6,7,8,9,11-decahydroanthracen-9-yl; 9,9-dimethyl-1,2,3,4,5,6,7,8,9,10-decahydroanthracen-10-yl; 9,9-dimethyl-1,2,3,4,5,6,7,8,9,11-decahydroanthracen-10-yl, 4,7-dimethylindene, 4,5,6,7-tetrahydroindene; 3-methylcyclopentadienylsilane, 1,2-dimethylcyclopentadienylsilane, 1,3-dimethylcyclopentadienylsilane, 1,2,4-trimethylcyclopentadienylsilane, 1,2,3,4-tetramethylcyclopentadienylsilane, pentamethylcyclopentadienylsilane, 1,2,4-trimethylindenylsilane, 1,2,3,4-tetramethylindenylsilane and pentamethylindenylsilane and each of their equivalent ligands. Other Z moieties include the fully substituted or sterically hindered substituted moieties of the compounds identified in U.S. Pat. No. 5,541,349 as the L ligand therein, which disclosure is fully incorporated herein by reference.
When Z is cyclic, the ring may optionally be comprised of heteroatoms, such as nitrogen or oxygen. Z can be a 4-50 member non-hydrogen atom group, preferably a 4-10 membered fully substituted cyclic moiety or a sterically hindered moiety comprised of a single or fused ring system. Examples of any of the above compounds bonded through an alkylene group (usually 2 to 8, preferably 2 to 3, carbon atoms) are suitable as the Z moiety. Examples of such compounds include bis(4,5,6,7-tetrahydro-1-indenyl)ethane, 1,3-propanedinylbisindene, 1,3-propanedinylbis(4,5,6,7-tetrahydro)indene, propylenebis(1-indene), isopropyl(1-indenyl)cyclopentadiene, diphenylmethylene(9-fluorenyl)cyclopentadiene, isopropylcyclopentadienyl-1-fluoreneisopropylbiscyclopentadiene. A mixture of any of the aforementioned compounds may be used in the synthesis of the catalyst.
Most preferred as the Z moieties are alkyl substituted cyclopentadienyl compounds, and in particular the C1-C4 alkyl substituted cyclopentadienyl compounds such as the mono, tri, tetra, or penta methyl, ethyl, propyl, isopropyl, or t-butyl cyclopentadienyl compounds (e.g. dimethylcyclopentadienyl, methylcyclopentadienyl, tetramethylcyclopentadienyl, diethylcyclopentadienyl, t-butylcyclopentadienyl, and pentamethylcyclopentadienyl) and the hydroxy and C1-C4 alkyl substituted indenyl and fluorenyl compounds, such as tetramethylindenyl, tetrahydrofluorenyl, and octahydrofluorenyl.
Some examples of cyclic Z moiety structures are represented below: 
wherein Z is fully substituted with R groups or sufficient numbers of R groups to sterically hinder the aromatic Cxe2x80x94H bonds. The number of R groups may range from 1 to 8.
The catalyst used in the process of the invention is also comprised of one or more c) ligands. The catalyst contains at least 1 c) ligand, and preferably contains 2 or more c) ligands. The c) ligand is derived from a source of ligands capable of formally donating an electron pair to the transition metal a) and which dissociate thermally.
The c) ligand is derived from sources which donate electron density to the transition metal and which contain either a non-bonding pair of electrons or a bonding pair of electrons. By xe2x80x9cdonatingxe2x80x9d a pair of electrons is meant that the ligand does not transfer electrons to the metal, and upon dissociation, the electrons leave with the ligand. It is not necessary that the bond linkage occur between a coordinating atom and the metal center. The bond linkage may occur between the metal center and a xcfx80 bond or a xcfx80 coordinated ring, each of which can donate electron density to stabilize the oxidation state of the metal center M, or the bond linkage may be a "sgr" bond between a ligand atom and the transition metal center.
The c) ligand should be one which dissociates from the catalyst upon application of thermal energy. Since it is desirable to both increase product yield and reaction rates, not all of the ligands should be of the type which are tightly held to the transition metal center, and not all ligands should dissociate from the catalyst slowly or only at temperatures approaching the decomposition temperature of the catalyst. Accordingly, at least one of the ligands should thermally dissociate from the catalyst. By thermally dissociating is meant that the ligand is capable of dissociating from the metal center using thermal energy at temperatures below the temperature at which the b) moiety dissociates from the metal center, which would result in the degradation of the catalyst. In a preferred embodiment, the c) ligand dissociates from the metal center a) at temperatures below 250xc2x0 C. and above 70xc2x0 C. Evidence of thermal dissociation is to conduct the reaction in a dark room and in the absence of any co-catalyst or other ingredients beside the functionalizing reagent, the catalyst, the hydrocarbon, and a solvent.
The c) ligand can be broadly represented by the following structural formulas: 
wherein X and Y each independently represent one or more of H, C, B, S, N, Si, Sn, P, and As and combinations thereof, to which saturated or unsaturated, branched or unbranched alkyl, aromatic, alicyclic, or alkaryl groups may be bonded, and wherein X and Y may be bridged to form a cyclic arene compound which may contain branches, substituents, or fused aromatic rings, R represents one or more optional branches or substituents, and n represents an integer ranging from 0 to 8. The unsaturation between X and Y may be olefinic or acetylenic. However, X and Y may also be bound by a single covalent bond when X or Y is hydrogen.
An example of a fused Xxe2x80x94Y structure is represented by a 6 membered aromatic ring as shown in the structure below: 
Preferred c) ligands satisfying the above criteria are derived from a source of :PR3, :NRxe2x80x23, HSiR3, unsaturated aliphatic compounds, xcfx80 allyl, and xcfx80 arene compounds. More preferred c) ligands comprise a source of HSiR3, unsaturated aliphatic compounds, xcfx80 allyl and xcfx80 arene compounds. Most preferred are the unsaturated aliphatic compounds, xcfx80 allyl compounds, and the xcfx80 arene compounds, and especially the unsaturated aliphatic compounds and the xcfx80 arene compounds.
Tertiary phosphines suitable as the c) ligand include the mono and bisphosphines. Monophosphines are represented by the formula:
:PR3
wherein R is independently an aromatic of up to 14 carbon atoms, optionally substituted; or a C1-C40 alkyl or alicyclic group, optionally containing atoms other than carbon and hydrogen in the form of monovalent substituents which are preferably electron-withdrawing substituents such as halo, preferably the middle halogens chloro and bromo, nitro and trifluoromethyl. Examples of aromatic Rxe2x80x2 groups include phenyl, tolyl and naphthyl. The aromatic groups are optionally substituted aryl groups with halogen atoms and alkyl, aryl, alkoxy, carboxy, carbalkoxy, acyl, trihalogenmethyl, cyano, dialkylamino, sulphonylalkyl and alkanoyloxy groups.
Other specific examples of suitable phosphines are bis(1,1-dimethylethyl) phenylphosphine, dimethylphenylphosphine, cyclohexyldiphenylphosphine, dibutylphenylphosphine, methyldiphenylphosphine, triphenylphosphine, tri-n-butylphosphine, tris(4-tolylphosphine), tris(4-chlorophenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(3-methoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(4-triflurophenyl)phosphine, tris(4-fluorophenyl)phosphine and 2-carboxyphenyl diphenylphosphine, tri-p-tolylphosphine, tri-p-methoxyphenylphosphine, o-diphenylphosphinobenzoic acid, and in particular triphenylposphine, tributylphosphine, trimethylphosphine, triethylphosphine, tripropylphosphine, and any C1-C6 alkyl combination as an Rxe2x80x2 group, 1,2-bis (diphenyl-phosphino) ethane, 1,2-bis(diphenylphosphino) ethene, 1,3-bis (diphenylphosphino) propane, 1,3-bis(diethylphosphino) propane, 1,4-bis (diphenylphosphino) butane, 1,3-bis(di-isopropylphosphino) propane and 1,3-bis (di-p-methoxyphenyl phosphino) propane.
Tertiary amines suitable as the c) ligand are represented by the formula:
:NRxe2x80x23
wherein Rxe2x80x2 has the same meaning as R above with respect to :PR3, as well as the polyamines such as the diamines, triamine, and pentamines.
Examples of electron donating c) amine ligands include trimethylamine, triethylamine, tri-n-propylamine,. triisopropylamine,tri(n-butyl)amine, tri(isobutyl)amine, N,N-dimethylaniline, tributylamine,benzyldimethylamine, tris(dimethylaminomethyl)phenol, dimethylethanolamine, n-methylmorpholine, triethylene diamine, N-methylmorpholine,N-ethylmorpholine, diethyl-ethanol-amine, N-cocomorpholine,1-methyl-4-dimethyl-amino-ethylpiperazine, 3-methoxypropyldimethylamine,N,N,Nxe2x80x2-tri-methylisopropyl propylenediamine, 3-diethylamino propyl-diethylamine,dimethylbenzylamine, dimethylcyclohexylamine, 2-methylimidazole, 2-phenylimidazole,2-ethyl-4-methyl imidazole, 2,4,6-tris(dimethylaminomethyl)phenol, 1,4-diazabicyclo(2,2,2)-octane, 1,5-diazabicyclo(5,4,0)-undecane, dimethyldodecylamine, pyridine, 4-(1-butylpentyl)pyridine, quinoline, isoquinoline, lipdine, quinaldine, nonylpyridine, 2,6-lutidine, 2,4,6-collidine, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole,2-ethyl-4-methylimidazole,1-benzyl-2-methylimidazole,l-propyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole,l-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole,1-cyanoethyl-2-phenylimidazole, 1-guanaminoethyl-2-methylimidazole, N,N-dimethylaniline, N,N-dimethyltoluidine, N,N-dimethyl-p-anisidine, p-halogeno-N,N-dimethyl-aniline, 2-N-ethylanilino ethanol, tri-n-butylamine, pyridine, quinoline, N-methylmorpholine, triethanolamine, and N,N,Nxe2x80x2,Nxe2x80x2-tetramethylbutanediamine.
The source of unsaturated aliphatic compounds as the c) ligand must contain C and H, although heteroatoms may also be present in the compound, provided that not more than 1 heteroatom for every 6 carbon atoms are present. Any aliphatic compound containing unsaturation which dissociates from the transition metal center at a temperature lower than the temperature at which the b) moiety (Z group) dissociates, is a suitable compound for use as a ligand.
The aliphatic unsaturated compound may have from 2 to 32 carbon atoms, preferably from 2 to 8 carbon atoms, more preferably from 2 to 6 carbon atoms. The aliphatic unsaturated compound may be alicyclic or in a linear or branched non-ring structure. Mono- or poly- olefins straight or branched chain compounds are preferred, with mon-olefins being more preferred.
Suitable unsaturated aliphatic compounds as the c) ligand include mono-olefins such as the linear olefins made by the cracking of paraffin wax, commercial olefin products manufactured by ethylene oligomerization are marketed in the United States by Shell Chemical Company under the trademark NEODENE, linear internal olefins made by the chlorination-dehydrochlorination of paraffins, by paraffin dehydrogenation, and by isomerization of alpha-olefins, detergent-range internal or alpha, branched or unbranched, mono-olefins containing from about 8 to about 22 carbon atoms such as those in the carbon number range of C10 to C12, C11 to C15, C12 to C13, and C15 to C18, and ethylene, propylene, 1-butene, 2-butene, 1-pentene, 2-pentene, isopentene, hexene-1, 2-hexene, 3-hexene, 4-methylpentene-1, 2-methylpentene-1, 4-methylbutene-1, 1-heptene, 2-heptene, 3-heptene, 1-octene, 2-octene, 2-methylheptene-1, 4-octene, 3,4-dimethyl-3-hexene, 1-decene, and 1-dodecene, and so forth up to 32 carbon atoms ; dienes and trienes including butadiene, 1,3-pentadiene, 1,4-pentadiene, 1,3-hexadiene, 1,4-hexadiene, 1,5-hexadiene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, 1,9-decadiene 1,13-tetradecadiene, 2,6-dimethyl-1,5-heptadiene, 2-methyl-2,7-octadiene, 2,7-dimethyl-2,6-octadiene, 2,3-dimethylbutadiene, ethylidene norbornene, dicyclopentadiene, isoprene, 1,3,7-octaroriene, 1,5,9-decartriene, 4-vinylcyclohexene, vinylcyclohexane; divinylbenzene, and cyclic olefins including cyclopentene, cyclobutene, cyclohexene, 3-methylcyclohexene, cyclooctene, cyclodecene, cyclododecene, xcex75-cyclohexadienyl, xcex76-cycloheptatriene, xcex78-cyclooctatetracene tetracyclodecene, octacyclodecene, norbornene, 5-methyl-2-norbornene, 5-ethyl-2-norbornene, 5-isobutyl-2-norbornene, 5,6-dimethyl-2-norbornene, 5,5,6-trimethyl-2-norbornene; and acetylenic compounds such as acetylene, methylacetylene, diacetylene, 1,2-dimethylacetylene, eta 3-pentenyl, and norbornadiene.
Sources of the xcfx80 allyl compound may contain from 3 to 64 carbon atoms. The electronic configuration of the xcfx80 allyl is not particularly limited, but will generally take on the xcex73 state. Any xcfx80 allyl which dissociates from the transition metal center at a temperature lower than the temperature at which the b) moiety (Z group) dissociates, is a suitable compound for use as a ligand.
Specific examples of xcfx80 allyl compounds include allyl acrylate, 2-propen-1-ol, allylamine, allylbromide, allyl hexanoate, allyl cyanide, allyl carbonate, 1-allyl-4-hydroxybenzene, allyl-alpha-ionone, allyl isocyanate, allyl isothiocyanate, allyl thiol, allyl methacrylate, 4-allyl-2-methoxyphenol, 4-allyl-1,2-methylenedioxybenzene, allyl pelargonate, allyl sulfide, and allyl thioureas.
The xcfx80-arene compound may contain from 5 to 64 carbon atoms, preferably from 5 to 14 carbon atoms. The electronic configuration of the xcfx80 allyl and the n-arene compound is not particularly limited, and may take on the xcex73, xcex74, xcex75, xcex76, xcex77, and xcex78 states, and may also have any isomeric structure within each xcex7 configuration, including the W, U, and S configurations. Any xcfx80 arene compound, whether substituted, fused, or bridged, which dissociates from the transition metal center at a temperature lower than the temperature at which the b) moiety (Z group) dissociates, and which lacks aromatic Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, or contains sterically hindered Cxe2x80x94H bonds on the moiety directly bonded to the transition metal, is a suitable compound for use as a ligand. Reference can be had to the Z moiety substituents described above to determine suitable substituents to sterically hinder the presence of aromatic Cxe2x80x94H bonds on the c) ligand.
Suitable xcfx80 arenes as the c) ligand include divinylbenzene, p-xylene, 1,3,5-trimethylbenzene (mesitylene), 1,2,4-trimethylbenzene, 1,3,5-triisopylbenzene, 1,2,3,4-tetramethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene (durene), pentamethylbenzene, hexamethylbenzene, fluorene, dibenzostannepine, tellurophene, phenothiarsine, selenanthrene, phenoxaphosphine, phenarsazine, phenatellurazine, 1,2,3,4,4a,9a)-9-(phenylmethylidene)fluorene, and (1,2,3,4,4a,9a)-9-(3-phenyl-2-propenylidene)fluorene.
The source of c) ligand may also comprise compounds derived from polyalkylsilanes. Such silanes can be represented by the following formula:
Rxe2x80x3nSi
wherein Rxe2x80x3 is hydrogen, or has the same meaning as R above with respect to suitable phosphine compounds as the c) ligand, and n is an integer ranging from 3-4, provided that the silane contains no more than two hydrogen atoms bonded to the silicon atom.
Most preferred examples of the c) ligand are represented by the following structural formulas: 
wherein each Rxe2x80x2xe2x80x3 independently represents hydrogen or a saturated or unsaturated, branched or unbranched alkyl, aromatic, alicyclic, or alkaryl group having from 1 to 15 carbon atoms or one or more fused ring structures, more preferably hydrogen or a saturated, branched or unbranched alkyl group having from 1 to 8 carbon atoms, most preferably from 1 to 4 carbon atoms; and n represents the number of Rxe2x80x2xe2x80x3 groups and is an integer ranging from 2 to 6. The electronic configuration of the aromatic radical may be in the xcex74, xcex75, or xcex76 states.
Examples of these most preferred c) ligands include ethylene, propylene, 1-butene, 2-butene, 2-methyl-propene-1, 1,4-di-t-butylbenzene, 1,3,5-trimethylbenzene (mesitylene), 1,2,4-trimethylbenzene, 1,3,5-triisopylbenzene, 1,2,3,4-tetramethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene (durene), pentamethylbenzene, hexamethylbenzene, and di-t-butylbenzene. Among these, ethylene and alkyl substituted C6 compounds, such an tri-, tetra-, penta-, and hexa- C1-C4 alkyl substituted C6 are particularly suitable.
While mention has been made of employing c) ligands, any other compound known to act as a ligand may be used in addition to the c)ligand. Examples of additional ligands which may be bonded to the transition metal center include hydrogen, CO, phosphite, alkoxy, amido, aryloxide, phosphido, arsenic radical, carbonates such as CF3CO2xe2x88x92, sulfonates such as CF3SO3xe2x88x92, and silyl groups.
The total sum of electrons donated by the ligands and the valence electrons possessed by the transition metal is governed by the xe2x80x9ceighteen electron rulexe2x80x9d in most cases. This rule states that the most stable organo-metallic compounds tend to be those compounds in which the sum of the electrons donated by the ligands and the metal is eighteen. Those skilled in the art, however, know that there are exceptions to this rule and that organometallic complex compounds having a sum of 16, 17, 19, and 20 electrons are also known. Therefore, organometallic catalysts described herein in which the complexed metal M have a total sum of 16, 17, 18, 19, or 20 electrons in the valence shell and a residual net positive charge of 1, 2 or 3 are included within the scope of the invention.
The catalyst may be synthesized by any of the known literature methods. The halide of the metal-Z moiety can be synthesized by the methods described in C. White, A. Yates, P. M. Maitlis, Inorg. Synth. 1992, V29, 228-234, incorporated herein fully by reference. The catalyst may be manufactured by combining in any sequence, but preferably by combining c) with the reaction product of a) and b).
Commercially available Z moiety -complexed metals, such as cyclopentadienyl metals, are generally complexed with a ligand other than an olefin or aromatic ligand. A typical ligand in commercially available cyclopentadienyl metal compounds is xe2x80x94CO. Any known method for substituting one ligand for another may be used to prepare the catalyst. The synthesis and purification of the catalyst including the ligands can be performed according to the methods described in T. M. Gilbert, R. G. Bergman, Inorg. Synth., 1990, V.27, 19-22; K. Moseley, J. W. Kang, P. M. Maitlis, J. Chem.Soc. A, 1970, 2875-83; W. J. Bowyer, J. W. Merkert, W. E. Geiger, Organometallics, 1989, V.8, 191-198; and C. White, P. M. Maitlis, J.Chem.Soc.A 1971, 3322-3326, each of which are incorporated herein fully by reference. In general, a molar ratio of Z-metal halide salt moieties to the c) ligand compound, as determined by the desired number of ligand compounds bonded to the transition metal, are mixed together in the presence of an optional solvent and acid under heat at xe2x88x9278xc2x0 C. to 100xc2x0 C. for a time sufficient to fully exchange the halide ligands with the c) ligands, after which the product is cooled and the acid removed by distillation under vacuum. The resulting solid may be washed with water and filtered. An aqueous source of a weakly coordinating anion such as NH4PF6 is mixed with the filtrate to precipitate the desired product, which may then be washed with more water and dried.
Examples of acids useful as agents to ionically bond the halide to the complex include CF3COOH, RCOOH, CF3xe2x80x94SO3H, and other weakly coordinating acids. Examples of other anionic sources useful to precipitate the catalyst include NH4BF6, NH4AsF6, NH4OH, NBa4PF6, and the like.
The process of the invention selectively functionalizes a hydrocarbon with functionalizing reagent. The functionalizing reagent comprises any group having an electropositive atom capable of bonding to the metal center M and making a strong Exe2x80x94C bond where E is the electropositive element. The overall reaction is between the reagent containing the electropositive element Xxe2x80x94E and the carbon-hydrogen Cxe2x80x94H converting to an Xxe2x80x94H bond and a carbon-electropositive bond Cxe2x80x94E, where X can be hydrogen, another electropositive atom, or other sacrificial portion of the molecule. The electropositive element should be chosen such that the absolute value of the Cxe2x80x94H, Xxe2x80x94E, Cxe2x80x94E, and Xxe2x80x94H bond energies satisfy the following equation:
Cxe2x80x94H+Xxe2x80x94E less than Cxe2x80x94E+Xxe2x80x94H
Preferably, the functionalizing reagent comprises a source of boron. The source of -boron compounds include numerous boron alkyl, boron aryl, organoboron hydride, or organoboron halide compounds that are known and/or may be prepared in a known manner. The types of boron compounds and their methods of preparation are described in xe2x80x9cMechanism of the Complexation of Boron Acids with Catechol and Substituted Catecholsxe2x80x9d by Pizer, R. and Babcock, L., Inorganic Chemistry, vol. 16, No. 7 pp. 1677-1681 (1977); R. K. Boeckman et al. xe2x80x9cCatechol boron halides: . . . xe2x80x9d Tetrahedron Letter, 1985, 26, pp. 1411-1414; S. Pereira, M. Srebnik, Tetrahedron Lett. 1996, V37, 3283-3286; C. E. Tucker, J. Davidson, P. Knochel, J.Org.Chem., 1992, V.57, 3482; R. A. Bowie, O. C. Musgrave, J.Chem.Soc. 1963, 3945-3949; and Herbert C. Brown, xe2x80x9cOrganic Synthesis via Boranesxe2x80x9d, John Wiley and Sons, 1975, each incorporated herein fully by reference.
Typical representatives of suitable sources of boron compounds are polyalkylmonoboranes and diborane compounds or Lewis base adducts of diborane. Examples of monoboranes include sodium borohydride, potassium borohydride, lithium borohydride, sodium trimethylborohydride, potassium tripropoxy-borohydride, tetramethylammoniumborohydride, triphenylborane, sodium tetraphenylborate, lithium tetraphenylborate, sodium hydrido tris(1-pyrazol)borate, potassium dihydro bis(1-pyrazol)borate, lithium triethylborohydride, lithium tri-sec-butylborohydride, potassium tri-sec-butylborohydride, sodium cyanoborohydride, zinc borohydride, bis(triphenylphosphine) copper (I) borohydride, potassium tetraphenylborate, lithium phenyltriethylborate, lithium phenyltrimethoxyborate, sodium methoxytriphenylborate, sodium diethylaminotriphenylborate, and sodium hydroxytriphenylborate.
In general, boranes derived from olefin hydroboration are useful. These boranes can be triethylborane, dicyclohexylborane, dihexylborane, diethylborane, ethylborane, boron alkyls such as 9-bora-bicyclo-[3.3.1]nonane, diisopinocampheyl borane, dicyclohexyl borane, 2,3-dimethyl-2-butyl borane, 3,5-dimethylborinane and diisoamyl borane, diisopinocampheyl borane, thexylcyclohexyl borane, thexyllimonyl borane, and dinorbornylboron. Further suitable sources of mono-boranes are reaction products of 1,2-dihydroxybenzenes or 4,6-dimethyl, 1,2-dihydroxybenzenes with boron hydride (boryl catechol or boryl 4,6-dimethylcatechol) and tri-n-butyl boroxine. The boryl compounds in their halogenated state provide a synthetic route to making the functionalizing reagent. Boryl compounds may be reacted in their halo-form with the metal or organo-metallic compounds or complexes. An example of a type of haloboryl compound is the family of halocatecholborane, available commercially. Any halide is suitable, including Cl, Br, and I. The haloboryl compounds in this family may be prepared by reacting an R(OH)2 compound with BX3, where X is a halide.
Examples of structures for sources of haloboryl compounds are represented by the following formulas: 
Bis(dioxaborolane) compounds may be conveniently prepared by reduction of halodiaminoboranes using sodium metal, and subsequent reaction with diols in the presence of acid.
Preferred boron containing functionalizing reagents are the branched or unbranched, substituted or unsubstituted pinacol derivatives of mono- or di-boron. Other examples of diboryl adducts include tetrakis dimethylaminodiboron, biscatecholate diboron, and substituted bis-catecholate diboron. Preferred diboryl compounds contain a moiety represented by the following structural formula: 
In another embodiment, a preferred diboryl functionalizing reagent is represented by the structure: 
wherein each R1 independently represents an alkyl group having from 1 to 24 carbon atoms, alkoxy groups contain from 3 to 24 carbon atoms, a cycloaliphatic group containing from 3 to 8 carbon atoms, or an aryl group containing from 5 to 16 atoms, and each of the alkyl, aryl, alkoxy, and cycloaliphatic groups in the aforementioned dioxaborolane compounds may be linear or branched; or substituted with halogens, such as fluorine or bromine, or alkyl groups having from 1 to 16 carbon atoms, preferably from 1 to 4 carbon atoms, and optionally each R1 group attached to the same boron atom through oxygen atoms may be fused or bridged through any of the aforesaid alkyl, alkoxy, cycloaliphatic or aryl groups.
Examples of preferred bis(dioxaborolane) containing compounds include bis-pinacolate diboron and bis(t-butylcatecholate) diboron.
The hydrocarbon, preferably an alkane, is selectively functionalized at the primary Cxe2x80x94H site by simply combining the catalyst, functionalizing reagent and hydrocarbon under functionalizing reaction conditions. To initiate the reaction by dissociating the ligand from the catalyst, the reaction mixture is heated to any temperature above the temperature at which the catalyst is stored, or room temperature, whichever is less, and below the thermal decomposition temperature of the catalyst or functionalizing reagent. It is desirable that the reagent species employed activates at temperatures above those the reagent would encounter during shipping or storage to ensure storage stability. Accordingly, suitable reaction temperatures range from 70xc2x0 C. to about 250xc2x0 C., more preferably from 100xc2x0 C. to 200xc2x0 C.
While the molar ratio of ingredients is not critical, it is desirable to use a stoichiometric excess of functionalizing reagent over the metal catalyst ( greater than 1:1), and preferably a molar ratio of  greater than 10:1, and more preferably  greater than 100:1, and most preferably  greater than 200:1, respectively. The amount of catalyst is also not particularly limited. However, an amount of catalyst ranging from 0.1 to 10 mole %, preferably from 0.1 to 5 mole %, based on the combined moles of catalyst and hydrocarbon will operate to functionalize the hydrocarbon at the primary Cxe2x80x94H site. Other reaction conditions are not particularly limited.
The reaction time is not limited, other than the reaction time should be as short as possible to reduce. cycle time and increase throughput. Reaction times may range from 0.5 hours to 48 hours. The reaction may be carried out at any desired pressure. Pressures within the range of 0 p.s.i.g. to 100 p.s.i.g. are suitable. The reaction between the functionalizing reagent and the hydrocarbon in the presence of the catalyst may be carried out in any solvent for both the reagent and hydrocarbon. The process of the invention advantageously employs the hydrocarbon as the solvent for the functionalizing reagent without need to add additional solvent.
Once the reaction is complete, the functionalized hydrocarbon may be separated and isolated from the reaction mixture by distillation, chromatography, or crystallization.
The process of the invention is 80% or more selective toward functionalizing a primary Cxe2x80x94H bond on hydrocarbon molecules, in contrast to a secondary Cxe2x80x94H bonding site. Of the Cxe2x80x94H sites on the hydrocarbon which are converted, the process of the invention is capable of selectively functionalizing 90% or more, preferably 95% or more, and more preferably 98% or more, and most preferably 99% or more of the converted Cxe2x80x94H sites on the hydrocarbon at the primary Cxe2x80x94H site.
The process is also catalytic. The process of the invention enables one to thermally activate the catalyst while achieving 50 or more turnovers. The number of catalyst turnovers is calculated by dividing the moles of product made by the moles of catalyst added to the process. Preferably, the catalyst turns over more than 75 times, more preferably 100 times or more.
Without being bound to a theory, and for illustration purposes only, it is believed that one possible mechanism for the functionalization of the hydrocarbon, using B2pin2 and a Cp*Rh(C2H2)2 (Cp*=xcex75 C5Me5) and nonane as illustrative examples of the functionalizing reagent, catalyst, and hydrocarbon, respectively, proceeds according to the following catalytic cycles:
First Stage: B2pin2 as reagent: 
Second Stage: HBpin as reagent 
Once the hydrocarbon is functionalized as a boryl adduct of the hydrocarbon at a primary Cxe2x80x94H site, the adduct may be converted into any other hydrocarbyl containing functional group using well known and conventional processes, such as those described in H. C. Brown, xe2x80x9cHydroboration,xe2x80x9d 1962; R. C. Larock, xe2x80x9cComprehensive Organic Transformations; A Guide To Functional Group Preparations,xe2x80x9d New York, N.Y., 1989; and H. C. Brown, xe2x80x9cOrganic Synthesis via Boranes,xe2x80x9d New York, N.Y., 1975. For example, primary alcohols can be manufactured by the oxidation of the primary alkylboryl adduct using an alkali metal hydroxide solution in the presence of a peroxide, or the adducts may be carbonylated to an alcohol by reacting the primary alkylboryl adduct in the presence of carbon monoxide, water and an alkali metal hydroxide such as NaOH or KOH.
Carboxylic acids can be prepared by oxidation of the borane functionalized hydrocarbon to an alcohol, followed by conventional oxidation of the alcohol to the acid. Amine functional hydrocarbons can be prepared by reaction of borane functionalized hydrocarbon with o-hydroxylamine sulfonic acid and chloroaminexe2x80x9d
The functionalized borane hydrocarbons converted to xe2x80x94OH, xe2x80x94COOH, and xe2x80x94NH2 or xe2x80x94NHR bearing compounds may be further converted to hydrocarbons containing ester, amide, imide, carbonate and polycarbonate, sulfonate, ether, polyether, and glycidyl ether groups.